Immunocytochemical localization of gamma-glutamyltransferase in induced hyperplastic nodules of rat liver.

The immunocytochemical localization of gamma-glutamyltransferase [(5-glutamyl)-peptide:amino-acid 5-glutamyltransferase, EC 2.3.2.

Transepithelial endoplasmic reticulum in rat proximal convoluted tubule.

Inosine 5'-diphosphatase (IDPase) activity was demonstrated cytochemically in the endoplasmic reticulum of rat kidney proximal tubule cells in tissue fixed by perfusion with glutaraldehyde--formaldehyde. Incubation for IDPase activity at pH 7.2 was performed with and without 0.

Immunocytochemical localization of gamma-glutamyltransferase in rat kidney with protein A-horseradish peroxidase.

Immunocytochemistry with a specific antiserum and protein A-horseradish peroxidase permits visualization of the sites of gamma-glutamyltransferase [(5-glutamyl)-peptide:amino-acid 5-glutamyltransferase, EC 2.3.2.

Pyridoxal phosphatase: cytochemical localization in GERL and other organelles of rat neurons.

A phosphatase, hydrolyzing pyridoxal-5-phosphate (P5P), a physiologically active component of the vitamin B6 complex and an essential co-enzyme in the synthesis of neurotransmitters, has been localized cytochemically in the perikarya of neurons in the peripheral, autonomic and central nervous systems of the rat. Neurons in dorsal root ganglia, sympathetic ganglia and ventral horn of spinal cord were studied by light and electron microscopy, while Purkinje cells, neurons in the dentate nucleus of the cerebellum, thalamus, and hypothalamus were studied by light microscopy only. Optimal conditions for demonstrating this activity in aldehyde-fixed tissue were determined with dorsal root ganglia.

Adenosinetriphosphatase activity in the cell membranes of kidney tubule cells.

This cytochemical study demonstrates high levels of apparent ATPase activity in the infolded cell membranes of the proximal tubules (dog, rat, human, mouse, monkey, and opossum) and ascending loops of Henle (dog, rat, human and, to a variable degree, mouse). Electron microscopy has shown (see Rhodin (1)) that these membranes separate adjacent cells where they interlock with one another by multiple cytoplasmic lamellae containing oriented mitochondria. The significance of the high ATPase activity is considered in relation to possible movements of the membranes and to "active transport" believed to occur there.